Abstract

Background

The hypothalamic-pituitary-adrenocortical (HPA) axis and sympathetic adrenomedullary
(SAM) system are the major stress-response pathways. Plasma adrenocorticotropic hormone
(ACTH) represents HPA axis activity, while plasma catecholamines are used as markers
of the SAM system. Salivary alpha amylase (AA), chromogranin A (CgA), and immunoglobulin
A (IgA) are candidate markers of stress activation, although their role has not been
established. The Uchida-Kraepelin (U-K) test is a questionnaire that requires intense
concentration and effort, and has been used as a tool to induce mental stress. However,
it is not clear whether or not the test is effective as a psychological/mental stressor.

Methods

In this study, normal young women took the U-K test and serial measurements of plasma
ACTH and catecholamines (dopamine, noradrenaline, and adrenaline) (n = 10), as well
as salivary AA, CgA, and IgA (n = 16) before, during and after the test.

Results

We found no changes in any of these parameters at any time point during or after the
U-K test.

Conclusion

Our findings indicate that the U-K test is not a suitable for measuring the psychological/mental
stress of young women because the plasma data showed that it did not affect the HPA
axis and SAM system. The U-K test should be employed carefully as a psychological/mental
stressor due to insufficient scientific evidence of its effectiveness. In addition,
salivary AA, CgA, and IgA should not simply be compared with previous reports, because
the mechanism of secretion and normal range of each salivary parameter remain unknown.
Salivary AA, CgA, and IgA may not be suitable candidate markers of psychological/mental
stress.